Automatic electric-circuit controller



(No Model.)

T. P. CON ANT.

. AUTOMATIC ELECTRIC CIRCUIT CONTROLLER.

Patented Mar. 29, 1887.

vwewboz N. PETERS. PholoLilhogrqpher, Washington, D. C

UNITED STATES PATENT OFFICE.

THOMAS P. OONANT, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE ELECTRICAL ACOUMULATOR COMPANY, OF NEW YORK.

AUTOMATIC ELECTRIC- CIRCUIT CONTROLLER.

SPECIFICATION forming part of Letters Patent No. 360,375, dated March 29, 1887.

Application filed November ll, 1886. Serial No. 218,557. (No model.)

To aZZ whom it may concern.-

Be it known that I, THOMAS P. CONANT, a citizen of the United States, and a resident of Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Automatic Circuit-Gontrollers, of which the following is a specification.

This invention is intended to furnish apparatus for automatically controlling the circuit in which the energy of a primary electrical generator is conveyed to a secondary battery or accumulator. The requisite functions of such an apparatus are that it shall avoid the evil effects of a reverse current from the ac cumulator and preserve a substantially uni form intensity of current, removing or disconnecting the charging-generator if these conditions or limitations are departed from.

My invention comprises an electromagnetic instrument controlling means whereby the charging-circuit is not closed until the electro-motive force of the generator rises to a predeterminedpoint. XVhen the chargingcircuit is closed its further control is transferred to a second electromagnetic instrument operated by variations in the strength of current. These two electromagnetic instruments may serve the additional purpose of voltmeter and ammeter, respectively. To enable these two electromagnetic instruments to control the charging-circuit, as stated, I place a polarized electromagnet in a VVheatstone bridge forming part of the shunt-circuit to the dynamo. The armature of this eleetro magnet operates a circuit-closing point in the charging-circuit, and the voltmeter and ammeter control short circuits round resistances in the arms of the bridge. Normally, the bridge is balanced, and the circuitcloser controlled by the polarized magnet is open. When the dynamo is started, the voltmeter responds, and at a certain point in its movement momentarily removes a section of the resistance in one arm of the bridge. A current of a given polarity flows in the crosswire, the polarized electro-magnet operates the circuit-closer in the charging-circuit, and current flows in said circuit, operating the ammeter. As the voltmeter continues its movement,the bridgeis restored to its balance; but

the polarized armature maintains the position taken by it under the influence of the momentary starting-current, and control of the circuit passes to the ammet-er. The moving needle of the ammeter, as the current strength rises, takes up its position between two movable switch-arms, either of which arms are arranged, when operated to make and break a short circuit, round a resistance in the opposite side of the bridge from that controlled by the voltmeter, so that when the ammeter indicates too great a variation of current strength by an extraordinary excursion either up or down the scale, one or the other of the two switches will be operated to remove the resistance in said arm of the bridge, and a current will flow in the cross-wire in the opposite direction to the starting-current, and the polarized electro-magnet will be operated to open the chargingcircuit.

I will now describe my invention by referring to the accompanying drawing.

The dynamo D is intended 'to charge the secondary battery S B.

V is an electromagnetic device, consisting of a solenoid having a core, 0, jointed to a pivoted' lever, d, carrying an adjustable weight, w. A pivoted pointer, 0, indicates upon a scale, s, the electro-motive force in the shuntcircuit 1. When the dynamo is started, the

solenoid attracts its core 0, and the arm 0 in its upward movement engages with the springretracted switch-arm a, causing it to make contact with the stop 1) during the brief interval that arm 6 is passing arm a, after which a returns to its normal position.

A is a solenoid of coarser wire, located in the main circuit 3, and having a permanent magnet, c, for its core and operating-arms pivoted and arranged like those of thevoltmeter V. The solenoid A may be used as an ammeter. \Vithin the path of its arm 0 there are two switch-arms, w and 70, making contact with points 3 and Z, respectively. The arm einits upward movement raises and passes the arm x,- but should the currentstrength carry 6 into contact with It, that arm is moved into contact with Z. Should the'current, strength decrease sufiiciently to allow e to drop into contact with x, that arm is carried upon its contact-stop y.

ICO

. switches Z k and x y.

Bridge WV is in a shunt-circuit, 2, from the dynamo. In the cross-wire of the bridge is a polarized electro-magnet, P, having an armature, 1), operating contact-points m-such as mercury-cups and a connecting-wire-to make and break the main circuit 3. The armature '15 19 has no bias, and will rest upon either side to which it may be carried.

The shunt-circuits l and 2 are continually closed. Normally the bridge is balanced, no current flows in the cross-wire, and the contact-points m are open. When the dynamo is started, the core 0 of voltmeter V is gradually attracted. As the electromotive force rises, the arm e is carried upward, and when it has reached a predetermined point engages with switchbar a, causing it to make contact with b, closing circuit 5 6 and short-circuit ing resistance r. The bridge is now out of balance, and a current flows in the cross-wire, operating the polarized electro magnet P, which closes the circuit-closer m, and current flows in the charging-circuit 3. Arm 0 of voltmeter V has continued to rise with the increasing electro-motive force and is now above the switch-arm a, arm a has resumed its normal position, and the bridge is again balanced. Polarized arm 1), however, remains in the position to which it was carried by the startingcurrent in the cross-wire and the circuit-closer remains closed. The ammcter A, under the influence of the current flowing in the main circuit, attracts its core, which, as it rises, car- Iies arm e past switch-arm :0, and has a range of movement under fluctuation of the current between the limits indicated by the location of the switch arms m and 70. rise above this limit, 6 engages with k, carrying it upon its contact Z, closing the-short circuit 6 7 round resistance It. Current now flows in the cross-wire in an opposite direction to that taken by the starting-current, the position of the polarized armature 1) is changed, and circuit is broken at m. The switch Z k is so arranged that the arm k is driven up an inclined surface on Z and remains there till 'removed by hand. If the current should] decrease below its limit, the same operation takes place with respect to switch 00 3 Such fall in the current strength may, of course, be due to the failure of the generator or the abnormal increase in the electro-motive force of the storage-battery.

The circuit 2, including the bridge, is, for convenience, shown as connected with the generatorD; but obviously the bridge-circuit may be (and under some circumstances preferably would be) fed by an independent generator,

Should the current as a battery. For example, the bridge may be connected in a local circuit indicated by the dotted line 8, said circuit including a local battery, L B.

The electromagnetic instruments V and A may be of any suit-able construction adapted to make electrical contacts, substantially as shown, and are preferably calibrated to reg1ster upon scales 8 variations in the electrical current.

I sometimes prefer to vary the form of electromagnetic instrument in the bridge, and to use a small electromagnetic motor having its armature-coil in the cross-wire and its fieldcoils in the first and second sides or arms of the bridge.

The amount of resistance removedfrom one side of the bridge by the operation of voltmeter V is but a fractional part of the whole, while the operation of the ammcter A removes the entire amount from the opposite side. This is designed to insure avariation in the balance in case A and V should at any time operate simultaneously.

What I claim, and desire to secure by Letters Patent, is-

1. The combination of an electric generator and an electro-magnet in one main circuit, an electromagnetic instrument in a local circuit operating break-points in the main circuit, and electrical connections between contact points controlled by the first-named magnet and points in the local circuit, whereby the operation of the second magnet is controlled.

2. The combination of an electric generator and an electromagnet in one main circuit, an electro-magnet in a shunt-circuit, an electromagnet in alocal circuit, and electrical connections between contact-points operated by the first two magnets and points in said local circuit, whereby the operation of either of the,

two first-named magnets operates the magnet in the local circuit.

3. The combination of an electric generator and an electro-lnagnet in one circuit, an elec tro-magnet in a W'heatstone bridge forming part of a local circuit, and electrical connections between contact-points operated by the first-named magnet and points in the bridge, whereby the operation of the second electromagnet is controlled.

4. The combination of a generator of electricity, a secondary battery, and an electromagnct in one circuit, an electromagnetic switch in a lVheatstone bridge forming part of a local circuit, and electrical connections operated by the first-named magnet to vary the resistance of the bridge, whereby said switch is operated.

5. The combination of a generator of electricity supplying a main line, an electromagnet in a normally-elosed circuit uniting the opposite poles of an electromagnet in a \Vheatstone bridge forming part of a local circuit, and electrical connections between contact points operated by the first-named magnet and points in the bridge, whereby the operation of the second electro-magnet is controlled.

6. The combination of a generator'of electricity and a secondary battery in one main circuit, an electro-magnetic main-line switch in a local circuit, and two electro-magnets controlled by current from said generator operating contact points electrically connected with points in the local circuit, whereby the operation of said magnets causes the said switch to open and to close the main circuit, respectively.

7. The combination of a generator of elec tricity, an ammeter in circuit therewith, an electro-magnetic switch. operated by a local circuit to make and break the main circuit, and two circuit-closers in the local circuit operated by the indicator of the ammeter at opposite limits of its movement.

8. The combination of an electric generator and a storage battery in one circuit, a voltmeter in a shunt-circuit, an electro -magnetic switch in a local circuit, and a circuit-closer in the local circuit operated 'by the indicato of the voltmeter.

9. In an automatic circuit-controller, the combination, with the main circuit containing a dynamo-electric machine, storage-battery, and an ammeter, of ashunt-circuit containing a voltmeter, a shunt-circuit containing an electro-magnet operating break-points in the main circuit, a circuit-closer operated by the voltmeter, and a circuit-closer operated by the ammetcr in the last-named circuit.

10. In an automatic circuit-controller, the 5 combination, with the main circuit containing a dynamo-electric machine, a storage-battery, and an ammeter having a moving pointer, of a shunt-circuit containing an electro-magnet operating break-points in the main cir- 4o cuit, and two circuit-closers connected to the shunt-circuit operated by the pointer of the ammeter at opposite limits of its movement.

11. The combination of a charging-generator, a secondary battery in the main circuit 5 thereof, a circuit-breaker in said circuit, an electro-magnet, and a movable arm or circuitcontroller actuated by said magnet and adapted to operate said circuit-breaker when impelled to either limit of its motion by an abnormal increase or decrease of the current strength, substantially as described.

12. The combination of a generator of electricity supplying a main circuit, an electromagnet in a shunt-circuit, an electro-magnet in a local circuit operating break-points in the main circuit, and electrical connections between the contact-points operated by the firstnamed magnet and points in the local circuit, whereby the operation of the second magnet is controlled.

Signed at New York, in the county of New York and State of New York, this 10th day of November, A. D. 1886.

THOMAS P. CONANT.

Witnesses:

WM. B. VANSIZE, DANIEL E. DELAVAN. 

